Precipptation of resin from residual oils



Patented Aug. 23, 1932 I UNITED {STATES manner; a. asms, or nnooxtyn, NEW YORK; nssreuon TQ connusrion 1m "soonronnrromor NEW YORK, n. Y.,VA1COB2EORATIO1\T or MAINE I RESIN FROM RESIDUAL OILS N Drawing.

ate with lformalingin the presence of a suitable catalyst. When tar oils, such as a low temperature tar distillate or the tar acid con ,taining fractions of a coke oven tar, are heated with formalin orfits equivalent in the lapresence of a basic catalyst, a soluble and (fusible (FNtype) condensation product of the tar, acid and the formaldehyde is precipitated'. 'On subsequent heating this condensation product may be converted toan insolubie, i'n'fusible I ('G type) resin. Ithas been observedthat the hydrocarbon oil component of 'thetar distillate or fraction thus ftreated, most of which remains as a residual oil after precipitation ofthe condensation product, usually retains an appreciable portio'n cit {condensation product in solution or colloidal suspension. Recovery of the portion ofcondensation product thus remaining in suspensioni n the residual oil hasbeenlatltemp ted' in various-wayafor example by distillation treatment. All methods heretofore proposed for efiecting separation of the portion ofc ondensaition product thus remaining colloidai suspension or solution in the re- 3 1 sidua1 oilrhave proven tote im racticable; usually'hecau'se the treatment "impai ed the quality of the resins in omeway, asby subfijlectin'g them to heat sufficient to convert them into an insoluble form. The quantity of @"resin's thus retained in suspension or solutioni'in "the residual oil often represents a very. considerable proportion --'(.up to to of the theoretical yield from thecoal taritreatedg Accordingly recoveryof: this j portioniof the condensation product from a pncatiuncmu November 26,1928. serial No. 322,096.

the residual oil is: exceedingly desirable both from the standpoint of increasing the yield of the condensation product and also from the standpoint of. effecting purification of the residual oil to enable its further utilization. a V

The primary object of the present invention is to provide a process whereby the re- Qcovery of soluble and fusible resins from a solution or colloidal suspension thereof in hydrocarbon oil may be effected without impairment of the quality either of the resins or of the purified oil.

This invention 1s basedon the discovery that by intimately mixing with a dilute mineral acid solutionvthe residual oil remaining after aformaldehyde condensation treatment of a high or-lowtemperature tar distillate and the separationof the said oil'layer from the aqueouslayer and the precipitated -condensation product, 'it'is possible to effect substan tially complete separation from such residual oil of any soluble and fusible (A type) resin associatedtherewith without impairing the: qualities either of the oil or of the resin.

The neutral oil resultingfrom the treatment contains substantially no resinsin solution'or suspension and can be used for many purposes withlittle or no further treatment. For exampleit maybe used directly as a fuel oil; andit may be used as a spray oil and plant insecticide when emulsified with water preferably with the aid of an emulsifying: agent such as a water soluble soap, sulphonic acid, or the like. The dilute mineral acid employed in the treatment separates by simple gravity settling. into an aqueous layer which can be drawn ofi, filtered if necessary, and

reused While the preferred reagent'for use in efiect'ingw the separation of the resin from 1- residual oil is a dilute mineral acid solution ,such as hydrochloricor sulphuricacid,

the invention contemplates the use of other materials (forQeXample salts of aluminum, 1 iron and [other polyvalent metals such as ferto V ric chloride) capable of breaking down the colloidal suspension of the resin in the oil and of thereby precipitating the resin out of the residual oil.

Following is a. specific example illustrating a preferred method of carrying out the invention: 1000 cc. of the hydrocarbon oil residue remaining after a formalin condensation treatment ofa primary tar distillate having a boiling range up'to 300 C; was shaken with 150 cc. of a hydrochloric aCld'SOlHtl0I1. The neutral oil-acid mixture was then allowed to stand for a brief period until separation of the, resins occurred. The resinsliberated from the 'oil'bythe above treatment rapidly settledto the bottom of the vessel, and purified neutral oil separatedin a layer at the top of the vessel, while the acid treating-solupurified oil and the separated resin. The "resin layer was drawn 0E and dried on a steam bath and was found to represent about of the weight'of the main body of resin formed during the original formalin conden- "sation treatment of the tar distillate. The aqueous acid layer was then drawn off and setaside for use in treating another batch of residual oil. The purified oil contains no resin in suspension 'or'solution and compares $0 favorably in purity and-color with other hydrocarbon oils of similar gravity and boiling point range.

The purified neutral oil or residual oil has a relatively low viscosity, a specific gravity of substantially .92-.93, a sulphonation residuevalue of from 33 to 39%, and is substantially free from resinous condensation products. j As previously indicated, it may be'employed without further treatment as a fuel 40 oil; and it may also be employed as the base -"for plant insecticides and lubricants, when suitably emulsified with water by means of theusual emulsifying agents such as watersoluble soaps and the like;

the above example a dilute solution of sulphuric acid of equivalent strength can be substituted therefor. V

1 Similar results were'obtained on treating the oil residue remaining after a formalin condensation of a high temperaturecoal tar distillate with a dilute sulphuric acid solution' or with equivalent demulsifying agents such as those disclosed above. 7

The invention having been thus described,

"what is claimed as new is:

'L The' method of recovering heat-sensitive, soluble and fusible resins of the phenol formaldehyde potentially reactive type from a colloidal suspensionthereof in the hydro carbon oil components of a tar distillate, which comprises treating the said suspension with a' chemical treating agent capable of disrupting the suspension and of precipitating the resin therefrom, separating the thus tion formed an aqueous layer .between the:

Instead of using dilute hydrochloric acid in precipitated resin, and carrying out the said treatment and the step of separation respectively at temperatures'sufficiently low to prevent substantial conversion of the heat-sensiv tive resins into the insoluble, infusible form. 2. The method of recovering solubleand fusible synthetic resins of the phenol formaldehyde type from a colloidal suspension thereof in the hydrocarbon components of a' tar distillate, comprising treating the sus-" pension with a {dilute aqueous solution of a mineral acid,'thereby' disrupting the suspension and precipitating the soluble and fusible resins, separating from the purified oil the resins'thus liberated,ian"d employing temperatures s'ufliciently' 'lowthroughout"'the said trea ing stepv and; therist p f separation to prevent substantial conversion of the resins into 7 the insoluble,- 'infusible form. a 1' s" 3. In the process ofproducing fusible,

basic catalyst for the' condensation reaction and the resultant reaction mixture is sepa} rated into a plurality of layers,'on'e of which contains hydrocarbon oil having in colloidal solution therein a substantial amountof the said fusible, soluble, resinous condensation product, the steps which comprise treating the said hydrocarbon oil layer with a solution of a demulsifying agent for the colloidal so lution while preventing the conversion of the,

condensation .productsto the infusible' form, and separating from the {residual oil the having in suspension a substantialamount' of 7 4.111 the method of preparing a purified, substantiallyresin-free hydrocarbon oil from a tar oil containing tar acids in which the said ,tar oil is treated with an aldehyde-containing substance anda basiccatalyst 'for'thef condensation reaction and the resultant reaction mixture is separated into aplurality of layers, one of which containsfhydrocarbonoil resinous condensation "products thus liberate V the said resinouscondensation product in poitentially reactive form, the steps 'wh'i'ch'com-e pr se treating the unheated hydrocarbon; oil

layer with a solution of a demulsifying agent "for the said suspension, and separating from the hydrocarbon oilfthe thus precipitated product while maintainingthelatter in such unconverted form. v 'f 5. The method "of 1 recovering in soluble,

fusible'form, a synthetic" resin'of the phenolpotentially reactive resinousj condensation formaldehyde potentially-reactive type from.

a suspension thereof-in the hydrocarbo'ncomponents of a low temperature tar] distillate having a boilingrange up to 300916;, which comprises treating the said suspension with 1 approximately 7 15% by volume of a dilute;

' aqueous solution of a mineral acid in amounts 7 MADHAV R. BHAGWAT. 

